BRAIN TUMOR STUDY

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心机构，不一定为研究者机构。本项目的目的是评估扩散张量成像（DTI）诊断脑肿瘤的有用性。虽然传统的MRI技术一直发挥着至关重要的作用，但有几个重要的问题是它们无法回答的。这些信息包括关于肿瘤的边界及其生长特性的信息。例如，重要的是要知道肿瘤是离散生长还是浸润到邻近组织中，如果是浸润，浸润的方向是什么。作为初步研究，DTI应用于两例星形细胞瘤。肿瘤表现为低扩散各向异性和高扩散常数。与传统的T2加权像相比，由于肿瘤的扩散各向异性与正常灰质相似，因此DTI图像在识别和描绘肿瘤边界方面并不具有上级优势。另一方面，弥散张量成像可显示肿瘤生长引起的周围白色物质束的详细解剖结构。结果清楚地显示，其中一名患者的肿瘤离散生长，引起大量解剖变形，而另一名患者的肿瘤未引起显著的白色物质变形，表明肿瘤浸润。浸润的方向与称为上级纵束的主要联合束的轨迹一致。初步研究表明，弥散张量成像是一种很有前途的技术，以精确描绘脑肿瘤患者的神经解剖畸形。这些信息预计将用于手术计划，以避免损伤关键的白色物质束，并通过预测肿瘤扩散的方向用于治疗设计。研究结果发表在Annals of Neurology（51，377，2002）上。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The aim of this project is to assess the usefulness of diffusion tensor imaging (DTI) to diagnose brain tumors. While conventional MRI techniques have been playing crucial roles, there are several important questions that cannot be answered by them. These include information about the boundary of tumor and their properties of growth. For example, it is important to know whether a tumor is growing discretely or infiltrating into neighboring tissues and, if it is infiltrating, what is the orientation of the infiltration. As a preliminary study, the DTI was applied to two patients with astrocytoma. The tumors showed low diffusion anisotropy and high diffusion constant. Compared to conventional T2-weighted images, the images obtained from the DTI are not superior to identify and delineate the boundary of the tumors because the diffusion anisotropy of the tumors is similar to that of normal gray matter. On the other hand, the DTI could reveal detailed anatomy of nearby white matter tracts, which were deformed by growth of the tumor. The results clearly showed that the tumor in one of the patients was growing discretely inducing a large amount of anatomical deformation while the tumor in the other patient did not induce significant white matter deformation, indicating the infiltrating tumor. The orientation of the infiltration coincided with the trajectory of a major association tract, called superior longitudinal fasciculus. This preliminary study suggests that the DTI is a promising technique to precisely delineate deformed neuroanatomy of brain tumor patients. The information is expected to be used for surgical planning to avoid injuring critical white matter tracts and for treatment design by predicting the orientation of the tumor spreading. The result was published in Annals of Neurology (51, 377, 2002).